Organic light-emitting display and method of manufacturing the same

ABSTRACT

An organic light-emitting display and a method of manufacturing the organic light-emitting display are disclosed. In one embodiment, the organic light-emitting display includes: i) a pixel electrode disposed on a substrate, ii) an opposite electrode disposed opposite to the pixel electrode, iii) an organic emission layer disposed between the pixel electrode and the opposite electrode; a light-scattering portion disposed between the substrate and the organic emission layer, including a plurality of scattering patterns for scattering light emitted from the organic emission layer in insulating layers having different refractive indexes. The display may further include a plurality of light absorption portions disposed between the light-scattering portion and the organic emission layer to correspond to the scattering patterns.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application claims the benefit of Korean Patent Application No.10-2011-0079148, filed on Aug. 9, 2011, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

The described technology generally relates to an organic light-emittingdisplay and a method of manufacturing the same.

2. Description of the Related Technology

Organic light-emitting displays are attracting attention as nextgeneration displays because they are not only driven at a low voltage,are light and thin, and have wide viewing angles and excellent contrast,but also have quick response times.

SUMMARY

One inventive aspect is an organic light-emitting display that ismanufactured using a simple process and has a reduced color shiftaccording to a viewing angle, and a method of manufacturing the organiclight-emitting display.

Another aspect is an organic light-emitting display that is manufacturedusing a simple process and has an improved color shift according to aviewing angle by applying a resonance structure including a plurality ofscattering patterns, and a method of manufacturing the organiclight-emitting display.

Another aspect is an organic light-emitting display including: a pixelelectrode disposed on a substrate; an opposite electrode disposedopposite to the pixel electrode; an organic emission layer disposedbetween the pixel electrode and the opposite electrode; alight-scattering portion disposed between the substrate and the organicemission layer, including a plurality of scattering patterns forscattering light emitted from the organic emission layer in insulatinglayers having different refractive indexes; and a plurality of lightabsorption portions disposed between the light-scattering portion andthe organic emission layer to correspond to the scattering patterns.

Each of the light absorption portions may include a semiconductormaterial.

The plurality of insulating layers included in the light-scatteringportion may include at least a single pair of high and low refractiveindex layers.

The high refractive index layer may include silicon nitride, and the lowrefractive index layer comprises silicon oxide.

The scattering patterns may be formed in the high refractive indexlayer.

The plurality of scattering patterns may be spaced apart from oneanother.

The plurality of scattering patterns may be spaced apart from oneanother at constant intervals.

Each of the scattering patterns may be patterned to have a circularshape.

The organic light-emitting display apparatus may further include aninsulating layer disposed on the light-scattering portions to cover thelight absorption portions.

The insulating layer covering the light absorption portions may includeat least a single pair of high and low refractive index layers.

The high refractive index layer comprises silicon nitride, and the lowrefractive index layer may include silicon oxide.

The organic light-emitting display apparatus may further include a thinfilm transistor disposed on the substrate to be spaced laterally withrespect to the pixel electrode and including an active layer, a gateelectrode, and source and drain electrodes; and a capacitor includingupper and lower electrodes.

The active layer of the thin film transistor may include the samematerial as the light absorption portions.

The lower electrode of the capacitor may include the same material asthe light absorption portions.

The insulating layer covering the light absorption portions may bedisposed to extend between the active layer and the gate electrode andbetween the lower electrode and the upper electrode.

The light-scattering portion may be disposed to extend under the activelayer and the lower electrode.

The scattering patterns included in the light-scattering portion may bedisposed only in an area corresponding to the pixel electrode.

Another aspect is a method of manufacturing an organic light-emittingdisplay, the method including: forming a plurality of insulating layersincluding at least a single pair of high and low refractive index layerson a substrate and including a high refractive index layer at theuppermost position thereof; forming a plurality of scattering patternsfor scattering light by patterning the high refractive index layerdisposed at the uppermost position of the insulating layer; forming atleast one insulating layer covering the scattering patterns; forming amaterial that absorbs light on the insulating layer covering thescattering patterns; forming a plurality of light absorption portions bypatterning the material that absorbs light to correspond to thescattering patterns; forming an insulating layer covering the lightabsorption portions; and sequentially forming a pixel electrode, anorganic emission layer, and an opposite electrode on the insulatinglayer covering the light absorption portions.

The forming of the scattering patterns and the forming of the lightabsorption portions may be performed by using the same mask.

The forming of the scattering patterns may include: forming a pluralityof the scattering patterns; and forming the plurality of scatteringpatterns to be spaced apart from one another.

The plurality of scattering patterns may be space apart from one anotherat constant intervals.

Each scattering pattern may be formed to have a circular shape.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view of an organic light-emittingdisplay according to an embodiment.

FIGS. 2 to 9 are cross-sectional views sequentially illustrating amethod of manufacturing the organic light-emitting display of FIG. 1,according to an embodiment.

FIG. 10 is a schematic cross-sectional view of an organic light-emittingdisplay according to another embodiment.

FIG. 11 is a schematic cross-sectional view of an organic light-emittingdisplay according to another embodiment.

FIG. 12 is a schematic cross-sectional view of an organic light-emittingdisplay according to another embodiment.

DETAILED DESCRIPTION

In an organic light-emitting display, a voltage is applied between ananode and a cathode, electrons and holes combine in an organic lightemission layer disposed between the anode and the cathode so thatexcitons are formed therein and emit light while the excitons changefrom an excitation state to a ground state.

An organic light-emitting display has a wide emitting wavelength range,thereby reducing luminous efficiency and reducing color purity. Sincelight emitted from an organic emission layer has no directivity, manyphotons from among photons emitted in a predetermined direction do notreach a viewer due to total internal reflection, thereby reducingextraction efficiency of an organic light-emitting device. Thus, inorder to improve luminous efficiency, a resonance structure is formed inan organic light-emitting display by using a distributed Bragg reflector(DBR) mirror or by adjusting the thickness of an organic layer. However,although the resonance structure improves luminous efficiency, colorshift according to a viewing angle may still occur.

Now, embodiments will be described in detail with reference to theaccompanying drawings.

FIG. 1 is a schematic cross-sectional view of an organic light-emittingdisplay 1 according to an embodiment.

Referring to FIG. 1, a light-scattering portion 20 including a pluralityof insulating layers 20-1, 20-2, 20-3, and 20-4 is disposed in a pixelarea PXL on a substrate 10, the insulating layer 20-3 includingscattering patterns. A plurality of light absorption portions 130 aredisposed on the light-scattering portion 20 to correspond to thescattering patterns of the insulating layer 20-3, and a first pixelelectrode 151, an organic emission layer 91, and a opposite electrode 92are sequentially disposed on the light absorption portions 130. In oneembodiment, the light absorption portions 130 are substantially directlyformed above the scattering patterns of the insulating layer 20-3.

A thin film transistor area TFT and a capacitor area CAP are disposed ona side of the pixel area PXL. The thin film transistor area TFT includesan active layer 230, a first gate electrode 251, and a second gateelectrode 252, and source and drain electrodes 271 and 272 over thesubstrate 10 and the capacitor area CAP includes a lower electrode 330and a first upper electrode 351 over the substrate 10.

The substrate 10 may be formed of a SiO₂-based transparent glassmaterial. The substrate 10 may be formed of any of various materials,for example, transparent plastic.

The light-scattering portion 20 includes the insulating layers 20-1,20-2, 20-3, and 20-4 including at least a single pair of high and lowrefractive index layers. In the current embodiment, the light-scatteringportion 20 includes four insulating layers Furthermore, a highrefractive index layer is disposed at a lowermost position, and a lowrefractive index layer, a high refractive index layer, and a lowrefractive index layer are sequentially stacked on the high refractiveindex layer. The light-scattering portion 20 may also alternatelyinclude two or more layers having different refractive indexes. The lowand high refractive index layers, which are alternately disposed,improve light extraction efficiency and a color reproduction range ofthe organic light-emitting display 1 by forming a distributed Braggreflector (DBR) resonance structure.

The high and low refractive index layers denote layers having relativerefractive index differences. The high refractive index layer may beformed of a material selected from the group consisting of SiN_(x),TiO₂, Si₃N₄, Ta₂O₄, and Nb₂O₅, and the low refractive index layer may beformed of a siloxane-based material or SiO₂. When a plurality of highrefractive index layers are disposed, the high refractive index layersmay be formed of the same material or different materials, which mayalso be applied to the low refractive index layer.

The insulating layer 20-3 includes the scattering patterns forscattering light emitted from the organic emission layer 91. Theinsulating layer 20-3 including the scattering patterns may be a highrefractive index layer.

The organic light-emitting display 1 of the current embodiment includesthe scattering patterns only in an area corresponding to the pixel areaPXL. Although the insulating layer 20-3 is completely etched and thus isnot in the thin film transistor area TFT and the capacitor area CAP,embodiments are not limited thereto.

There are a plurality of the scattering patterns, which may be spacedapart from one another at constant intervals, for example. Also, ascattering pattern may have a circular shape, that is, a convex shape,for example, a lens. The scattering pattern may also have a crosssection having various shapes, for example, a triangular shape, aquadrangular shape, a pentagonal shape, a hexagonal shape, an octagonalshape, or the like. Although FIG. 1 illustrates three scatteringpatterns, four or more scattering patterns may be formed.

Light incident on the insulating layer 20-3 including the scatteringpatterns is diffusely reflected by the scattering patterns. Thus, colorshift of light laterally emitted may be reduced.

The light-scattering portion 20 may act as a DBR resonance structureincluding a plurality of scattering patterns to improve light extractionefficiency and to reduce color shift due to the DBR resonance structure.Also, the light-scattering portion 20 may act as a buffer layer toprevent impurities from the substrate 10 to penetrate therethrough andto planarize a surface of the substrate 10.

The light absorption portions 130 are disposed in the pixel area PXL onthe light-scattering portion 20. The light absorption portions 130 aredisposed to correspond to the scattering patterns included in thelight-scattering portion 20. The light absorption portions 130 may beformed of a semiconductor material such as amorphous silicon orpolysilicon. The light absorption portions 130 may also be formed of anyof various other materials capable of absorbing light.

A part of the light emitted from the organic emission layer 91 isincident on and absorbed into the light absorption portions 130.Accordingly, the light emitted from the organic emission layer 91 isdirectly incident on the scattering patterns included in thelight-scattering portion 20 and passes through the substrate 10, therebyreducing an intensity of the light directly emitted to the outside.Accordingly, since only light incident on areas other than the lightabsorption portions 130 is not absorbed by the light absorption portions130 and is emitted toward the light-scattering portion 20 and thus isscattered forward by the scattering patterns included in thelight-scattering portion 20, the light emitted to front and sidesurfaces of the organic light-emitting display 1 may be substantiallyuniformly distributed, thereby improving a viewing angle.

An insulating layer 40 is disposed on the light-scattering portion 20 tocover the light absorption portions 130. The insulating layer 40 mayinclude one or more materials selected from the group consisting ofSiO₂, SiN_(x), SiON, and the like. In the current embodiment, theinsulating layer 40 covering the light absorption portions 130 isconfigured as a single layer, for example.

The first pixel electrode 151, the organic emission layer 91, and theopposite electrode 92 are sequentially disposed on the insulating layer40.

The first pixel electrode 151 may be formed of a transparent orsemi-transparent conductive material. The transparent/semi-transparentconductive material may include at least one material selected from thegroup consisting of indium tin oxide (ITO), indium zinc oxide (IZO),zinc oxide (ZnO), indium oxide (In₂O₃), indium gallium oxide (IGO), andaluminium zinc oxide (AZO). Second pixel electrodes 152 may berespectively disposed on both edge portions of the first pixel electrode151. The second pixel electrode 152 may be formed of a metal materialselected from the group consisting of aluminum (Al), platinum (Pt),palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni),neodymium (Nd), iridium (Ir), chrome (Cr), lithium (Li), calcium (Ca),molybdenum (Mo), titanium (Ti), tungsten (W), and copper (Cu) to have asingle layer structure or a multi-layered structure. The second pixelelectrode 152 may protect the first pixel electrode 151 during amanufacturing process.

The organic emission layer 91 may be formed of a low molecular weightorganic material or a high molecular weight organic material. When theorganic emission layer 91 is formed of a low molecular organic material,a hole transport layer (HTL), a hole injection layer (HIL), an electrontransport layer (ETL), and an electron injection layer (EIL) may bestacked around the organic emission layer 91, or alternatively, variousother layers may be stacked when required. In this regard, examples ofavailable organic materials may include copper phthalocyanine (CuPc),N,N′-di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB),tris-8-hydroxyquinoline aluminum (Alq₃), and the like. When the organicemission layer 91 is formed of a high molecular weight organic material,the organic emission layer 91 may further include a hole transport layer(HTL), in addition to an emissive layer (EML). The HTL may be formed ofpoly-(2,4)-ethylene-dihydroxy thiophene (PEDOT), polyaniline (PANI), orthe like. In this regard, examples of available organic materials mayinclude a polyphenylene vinylene (PPV)-based high molecular weightorganic material and a polyfluorene-based high molecular weight organicmaterial, and the like.

The opposite electrode 92 may be a reflective electrode including areflective material. In the current embodiment, the first pixelelectrode 151 serves as an anode, and the opposite electrode 92 servesas a cathode However, the first pixel electrode 151 may also serve as acathode, and the opposite electrode 92 may serve as an anode. Theopposite electrode 92 may include one or more materials selected fromthe group consisting of Al, Mg, Li, Ca, LiF/Ca, and LiF/Al. Since theopposite electrode 92 is a reflective electrode, light emitted from theorganic emission layer 91 is reflected by the opposite electrode 92,passes through the first pixel electrode 151 formed of atransparent/semi-transparent conductive material, and is emitted towardthe substrate 10. In this regard, the DBR resonance structure includedin the light-scattering portion 20 may increase light extractionefficiency and a color reproduction range of the organic light-emittingdisplay 1. Also, as described above, color shift of the organiclight-emitting display 1 may be reduced due to the light absorptionportions 130 and the scattering patterns included in thelight-scattering portion 20.

The active layer 230, the first and second gate electrodes 251 and 252that are insulated from the active layer 230, and the source and drainelectrodes 271 and 272 are disposed in the thin film transistor area TFTon the light-scattering portion 20.

The active layer 230 may be formed of a semiconductor material such asamorphous silicon or polysilicon, or may or may not be formed of thesame material as that for forming the light absorption portion 130. Whenthe light absorption portion 130 and the active layer 230 are formed ofthe same material, the light absorption portion 130 and the active layer230 may be substantially simultaneously formed by performing the samemask process, and thus a manufacturing process may be simplified, aswill be described below in detail. Impurity doped areas 230 a and 230 cdoped with impurities are disposed at both sides of the active layer230.

The first gate electrode 251 and the second gate electrode 252 may berespectively formed of the same materials for forming the first pixelelectrode 151 and the second pixel electrode 152 on the same level.

The insulating layer 40 covering the light absorption portions 130 ofthe pixel area PXL is disposed between the active layer 230 and thefirst gate electrode 251. That is, the insulating layer 40 is disposedto cover the active layer 230 and serves as a gate insulating layer of athin film transistor.

The source and drain electrodes 271 and 272 may be formed of one metalmaterial selected from the group consisting of Al, Pt, Pd, Ag, Mg, Au,Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W, and Cu to have a single layerstructure or a multi-layer structure. The interlayer insulating layers60 are disposed under the source and drain electrodes 271 and 272, andone of the source and drain electrodes 271 and 272 is connected to thesecond pixel electrode 152 via a via-hole C2 in the interlayerinsulating layer 60, and the source and drain electrodes 271 and 272 arerespectively connected to the impurity doped areas 230 a and 230 c ofthe active layer 230 via contact holes C3 and C4.

The lower electrode 330 and the first upper electrode 351 are disposedin the capacitor area CAP on the light-scattering portion 20. The lowerelectrode 330 may be formed of the same material as those for formingthe light absorption portions 130 and the active layer 230 on the samelevel and may be doped with impurities.

The first upper electrode 351 may be formed of the same material as thatfor forming the first pixel electrode 151 on the same level, and secondupper electrodes 352 formed of the same material as that for forming thesecond pixel electrodes 152 may be disposed on both edge portions of thefirst upper electrode 351.

The insulating layer 40 may be disposed between the lower electrode 330and the first upper electrode 351 to cover the light absorption portions130. The insulating layer 40 serves as a dielectric layer of acapacitor. In this regard, an electric capacitance of the capacitor isdetermined according to a permittivity, an area, and a thickness of theinsulating layer 40. Accordingly, the electric capacitance of thecapacitor may be controlled by controlling the thickness of theinsulating layer 40.

FIGS. 2 to 9 are cross-sectional views sequentially illustrating amethod of manufacturing the organic light-emitting display 1 of FIG. 1,according to an embodiment.

Referring to FIG. 2, the insulating layers 20-1, 20-2, and 20-3 havingdifferent refractive indexes are formed on the substrate 10. The currentembodiment includes three insulating layers 20-1, 20-2, and 20-3, forexample. From among the insulating layers 20-1, 20-2, and 20-3, theinsulating layer 20-3 disposed at the uppermost position may be a highrefractive index layer.

Referring to FIG. 3, scattering patterns are formed in the insulatinglayer 20-3 disposed at the uppermost position. Although FIG. 3 does notillustrate a manufacturing process in detail, a photoresist (not shown)is coated on the insulating layer 20-3, and then the insulating layer20-3 is patterned using a photolithography process using a first mask(not shown). A first mask process is performed by performing a series ofprocesses, for example, exposing of the first mask by using an exposingapparatus (not shown), developing, etching, and stripping or ashing.Hereinafter, the same description regarding a subsequent mask processwill be omitted.

In the current embodiment, the scattering patterns are formed only in anarea corresponding to the pixel area PXL, the insulating layer 20-3 iscompletely etched in the thin film transistor area TFT and the capacitorarea CAP, and the scattering patterns formed in the pixel area PXL areseparated from one another.

There are a plurality of the scattering patterns, which may be spacedapart from one another at constant intervals. Also, the scatteringpattern may have a circular shape, that is, a convex shape, for example,a lens. In order to form the scattering pattern in a circular shape, theabove-described first mask process is performed on the scatteringpattern and then heat may be additionally applied thereto.

Referring to FIG. 4, the insulating layer 20-4 may be additionallyformed to cover the scattering patterns. The insulating layer 20-4 maybe a low refractive index layer and may be configured as a multi-layerincluding a low refractive index layer.

Referring to FIG. 5, the light absorption portions 130 are formed byperforming a second mask process in the pixel area PXL on thelight-scattering portion 20 including the plurality of insulating layers20-1, 20-2, 20-3, and 20-4, the active layer 230 is formed in the thinfilm transistor area TFT, and the lower electrode 330 is formed in thecapacitor area CAP. The light absorption portions 130 are formed tocorrespond to the scattering patterns included in the light-scatteringportion 20.

The light absorption portions 130, the active layer 230, and the lowerelectrode 330 may be formed of the same material on the same level. Thesame material may be a semiconductor material such as amorphous siliconor polysilicon. The semiconductor material may be deposited on thelight-scattering portion 20 by using any of various deposition methods,for example, a plasma-enhanced chemical vapor deposition (PECVD) method,an atmospheric pressure CVD (APCVE) method, a low pressure CVD (LPCVD),or the like. The light absorption portions 130, the active layer 230,and the lower electrode 330 may be simultaneously formed by performingthe second mask process on the deposited semiconductor material.However, the light absorption portion 130 may also be formed of anymaterial capable of absorbing light and may be separately formed fromthe active layer 230 and the lower electrode 330.

Referring to FIG. 6, the insulating layer 40 is formed throughout theorganic light-emitting display 1 so as to cover the light absorptionportions 130, the active layer 230, and the lower electrode 330, and atransparent conductive material and a metal material are sequentiallydeposited on the insulating layer 40. Then, the first and second pixelelectrodes 151 and 152, the first and second gate electrodes 251 and252, and the first and second upper electrodes 351 and 352 aresimultaneously formed in the pixel area PXL, the thin film transistorarea TFT, and the capacitor area CAP by performing a third mask process,respectively.

The insulating layer 40 may include one or more materials selected fromthe group consisting of SiO₂, SiN_(x), SiON, and the like and may serveas a gate insulating layer of a thin film transistor and a dielectriclayer of a capacitor. The insulating layer 40 may be configured as asingle-layer or a multi-layer structure.

The first gate electrode 251 and the second gate electrode 252 may beformed to correspond to a center portion 230 b of the active layer 230.Both edge portions of the active layer 230 are doped with ion impuritiesby using the first and second gate electrodes 251 and 252 asself-aligned masks.

Referring to FIG. 7, the interlayer insulating layer 60 is formed on aresultant of the third mask process performed in FIG. 6. Then, a firstopening C1 and a via-hole C2 exposing the second pixel electrode 152,the contact holes C3 and C4 partially exposing the impurity doped areas230 a and 230 c of the active layer 230, and a second opening C5exposing the second upper electrode 352 of the capacitor are formed bypatterning the interlayer insulating layer 60 by performing a fourthmask process.

Referring to FIG. 8, the source and drain electrodes 271 and 272 areformed on the interlayer insulating layer 60 by performing a fifth maskprocess.

One of the source and drain electrodes 271 and 272 is connected to thesecond pixel electrode 152 via the via-hole C2, and the source and drainelectrodes 271 and 272 are connected to the impurity doped areas 230 aand 230 c of the active layer 230 via the contact holes C3 and C4,respectively.

When the source and drain electrodes 271 and 272 are formed, the secondpixel electrode 152 and the second upper electrode 352 are etched at thesame time. The forming of the source and drain electrodes 271 and 272and the etching of the second pixel electrode 152 and the second upperelectrode 352 may be substantially simultaneously performed by using thesame etchant or may be sequentially performed by using differentetchants.

After the etching is performed, the lower electrode 330 of the capacitoris doped with ion impurities.

Referring to FIG. 9, a pixel-defining layer 80 for defining the pixelarea PXL is formed on a resultant of the fifth mask process performed inFIG. 7, and the pixel-defining layer 80 is partially etched byperforming a sixth mask process, thereby forming a third opening C6exposing a part of the first pixel electrode 151.

The organic emission layer 91 and the opposite electrode 92 aredeposited on the first pixel electrode 151 exposed by the third openingC6, thereby completing the manufacture of the organic light-emittingdisplay 1 illustrated in FIG. 1. In this regard, the opposite electrode92, which is a common electrode, may be formed throughout the organiclight-emitting display 1.

FIG. 10 is a schematic cross-sectional view of an organic light-emittingdisplay 2 according to another embodiment. Hereinafter, differencesbetween the current embodiment and the above-described embodiment willbe mainly described.

Referring to FIG. 10, a light-scattering portion 20 includes in a pixelarea PXL a plurality of patterns 120-3 scattering light emitted from anorganic emission layer 91, a pattern 220-3 formed in a thin filmtransistor area TFT similarly to an active layer 230, and a pattern320-3 formed in a capacitor area CAP similarly to a lower electrode 330.

The patterns 120-3, 220-3, and 320-3 formed in the light-scatteringportion 20 are formed similarly to light absorption portions 130, theactive layer 230, and the lower electrode 330. Accordingly, a first maskprocess for patterning the light-scattering portion 20 and a second maskprocess for forming the light absorption portions 130, the active layer230, and the lower electrode 330 may be performed by using the samemask. Thus, in the current embodiment, the number of masks used in aprocess for manufacturing the organic light-emitting display 2 may bereduced, and the patterns 120-3 and the light absorption portions 130formed in the pixel area PXL may be easily formed to correspond to eachother.

FIG. 11 is a schematic cross-sectional view of an organic light-emittingdisplay 3 according to another embodiment.

In the organic light-emitting display 3 according to the currentembodiment, an insulating layer 40, which is formed to cover lightabsorption portions 130, an active layer 230, and a lower electrode 330of a capacitor, includes two layers, namely, a lower insulating layer 41and an upper insulating layer 42. The lower insulating layer 41 may be alow refractive index layer formed of a siloxane-based material or SiO₂,and the upper insulating layer 42 may be a high refractive index layerformed of one material selected from the group consisting of SiN_(x),TiO₂, Si₃N₄, Ta₂O₄, and Nb₂O₅.

However, the insulating layer 40 may include three or more layers, andvarious materials for forming the low refractive index layer and thehigh refractive index layer may be used. Alternatively, the materialsfor forming the low and high refractive index layers may be the same asthose for forming the low refractive index layer and the high refractiveindex layer included in the light-scattering portion 20. However, sincethe lower insulating layer 41 directly contacts the active layer 230,the lower insulating layer 41 may be formed to have a hydrogen contentlower than that in the upper insulating layer 42.

The insulating layer 40 includes the high and low refractive indexlayers formed alternately, so that the insulating layer 40 and thelight-scattering portion 20 together may form a DBR resonance structure,thereby further increasing light extraction efficiency and a colorreproduction range of the organic light-emitting display 3.

However, since the insulating layer 40 serves as a dielectric layer inthe capacitor area CAP, the insulating layer 40 may be formed not toothick so that the capacitance of the capacitor is not excessivelydecreased.

Also, in the organic light-emitting display 1 illustrated in FIG. 1, theinterlayer insulating layer 60 is formed to cover both edge portions ofthe first pixel electrode 151 and both edge portions of the first upperelectrode 351 of the capacitor, while in the organic light-emittingdisplay 3, the interlayer insulating layer 60 is patterned not to covera first pixel electrode 151 and a first upper electrode 351 of acapacitor. During an etching process for patterning the interlayerinsulating layer 60, the insulating layer 40 covering the lightabsorption portions 130 and a part of the light-scattering portion 20may be simultaneously etched.

According to the configuration of the organic light-emitting display 3,an aperture ratio of the pixel area PXL is increased, thereby increasingan area where light is emitted, and the lower electrode 330 of thecapacitor is not influenced by the interlayer insulating layer 60, andthus the organic light-emitting display 3 may be entirely doped withions.

FIG. 12 is a schematic cross-sectional view of an organic light-emittingdisplay 4 according to another embodiment.

Referring to FIG. 12, the organic light-emitting display 4 has the sameconfiguration as that of the organic light-emitting display 1illustrated in FIG. 1, except for a patterned insulating layer 20-3included in a light-scattering portion 20. The insulating layer 20-3illustrated in FIG. 1 is disposed only in the pixel area PXL andincludes the scattering patterns spaced apart from one another, whilethe insulating layer 20-3 of the current embodiment includes convexpatterns formed on a flat area to be spaced apart from one another. Theflat area of the insulating layer 20-3 extends to a thin film transistorarea TFT and a capacitor area CAP.

Light incident on the insulating layer 20-3 is scattered in an areawhere the convex patterns are disposed and is reflected or permeates inthe other areas according to a general condition.

According to the above-described organic light-emitting displays and themethod of manufacturing the displays, color shift according to a viewingangle can be reduced by applying a resonance structure including aplurality of scattering patterns.

While the above embodiments have been described with reference to theaccompanying drawings, it will be understood by those of ordinary skillin the art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the following claims.

What is claimed is:
 1. An organic light-emitting display comprising: apixel electrode disposed over a substrate; an organic emission layerdisposed on the pixel electrode; an opposite electrode disposed on theorganic emission layer; a light-scattering portion disposed between thesubstrate and the organic emission layer, wherein the light-scatteringportion comprises i) a plurality of insulating layers having differentrefractive indexes and ii) a plurality of scattering patterns configuredto scatter light emitted from the organic emission layer, wherein theplurality of scattering patterns overlap the pixel electrode in planview; and a plurality of light absorption portions separated from eachother and disposed between the light-scattering portion and the organicemission layer to correspond to the scattering patterns, respectively,wherein the number of the scattering patterns is the same as that of thelight absorption portions.
 2. The organic light-emitting display ofclaim 1, wherein each of the light absorption portions is formed of asemiconductor material.
 3. The organic light-emitting display of claim1, wherein the insulating layers comprise at least one pair of high andlow refractive index layers.
 4. The organic light-emitting display ofclaim 3, wherein the high refractive index layer is formed of siliconnitride, and wherein the low refractive index layer is formed of siliconoxide.
 5. The organic light-emitting display of claim 3, wherein thescattering patterns are formed in the high refractive index layer. 6.The organic light-emitting display of claim 1, wherein the scatteringpatterns are spaced apart from one another.
 7. The organiclight-emitting display of claim 6, wherein the scattering patterns aresubstantially evenly spaced apart from one another.
 8. The organiclight-emitting display of claim 6, wherein each of the scatteringpatterns has a circular shape.
 9. The organic light-emitting display ofclaim 1, further comprising an additional insulating layer disposed tocover the light absorption portions.
 10. The organic light-emittingdisplay of claim 9, wherein the additional insulating layer comprises atleast one pair of high and low refractive index layers.
 11. The organiclight-emitting display of claim 10, wherein the high refractive indexlayer is formed of silicon nitride, and wherein the low refractive indexlayer is formed of silicon oxide.
 12. The organic light-emitting displayof claim 9, further comprising: a thin film transistor disposed over thesubstrate to be spaced laterally with respect to the pixel electrode,wherein the thin film transistor comprises an active layer, a gateelectrode, and source and drain electrodes; and a capacitor comprisingupper and lower electrodes.
 13. The organic light-emitting display ofclaim 12, wherein the active layer is formed of the same material as thelight absorption portions.
 14. The organic light-emitting display ofclaim 12, wherein the lower electrode of the capacitor is formed of thesame material as the light absorption portions.
 15. The organiclight-emitting display of claim 12, wherein the additional insulatinglayer is disposed between the active layer and the gate electrode, andbetween the lower and upper electrodes.
 16. The organic light-emittingdisplay of claim 12, wherein the light-scattering portion is disposed toextend under the active layer and the lower electrode.
 17. The organiclight-emitting display of claim 16, wherein the scattering patterns aredisposed only in an area corresponding to the pixel electrode.
 18. Theorganic light-emitting display of claim 1, wherein the light absorptionportions are substantially directly formed above the scatteringpatterns, respectively.